Add Smoke Test

Signed-off-by: AKP <tom@tdpain.net>

go.mod

@@ -1,3 +1,8 @@
 module git.tdpain.net/codemicro/protohackers
 
 go 1.19
+
+require (
+	github.com/alexflint/go-arg v1.4.3 // indirect
+	github.com/alexflint/go-scalar v1.1.0 // indirect
+)

go.sum

@@ -0,0 +1,12 @@
+github.com/alexflint/go-arg v1.4.3 h1:9rwwEBpMXfKQKceuZfYcwuc/7YY7tWJbFsgG5cAU/uo=
+github.com/alexflint/go-arg v1.4.3/go.mod h1:3PZ/wp/8HuqRZMUUgu7I+e1qcpUbvmS258mRXkFH4IA=
+github.com/alexflint/go-scalar v1.1.0 h1:aaAouLLzI9TChcPXotr6gUhq+Scr8rl0P9P4PnltbhM=
+github.com/alexflint/go-scalar v1.1.0/go.mod h1:LoFvNMqS1CPrMVltza4LvnGKhaSpc3oyLEBUZVhhS2o=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

smokeTest/main.go

@@ -0,0 +1,80 @@
+package main
+
+import (
+	"fmt"
+	"github.com/alexflint/go-arg"
+	"io"
+	"net"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+type Config struct {
+	Address string `default:"127.0.0.1:9000"`
+}
+
+func main() {
+	conf := new(Config)
+	arg.MustParse(conf)
+
+	if err := run(conf); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "Fatal error: %v\n", err)
+		os.Exit(1)
+	}
+}
+
+func run(conf *Config) error {
+
+	stopSig := make(chan os.Signal, 1)
+	signal.Notify(stopSig, syscall.SIGINT)
+
+	listener, err := net.Listen("tcp", conf.Address)
+	if err != nil {
+		return err
+	}
+	defer listener.Close()
+
+	_, _ = fmt.Fprintf(os.Stderr, "Listening on %s\n", conf.Address)
+
+	connChan := make(chan net.Conn, 256)
+	go func() {
+		for {
+			conn, err := listener.Accept()
+			if err != nil {
+				_, _ = fmt.Fprintf(os.Stderr, "Failed to accept connection: %v", err)
+				return
+			}
+			connChan <- conn
+		}
+	}()
+
+loop:
+	for {
+		select {
+		case <-stopSig:
+			break loop
+		case conn := <-connChan:
+			go func() {
+				err := handleConn(conn)
+				if err != nil {
+					_, _ = fmt.Fprintf(os.Stderr, "Error when handling connection: %s: %v\n", conn.RemoteAddr(), err)
+				}
+			}()
+		}
+	}
+
+	return nil
+}
+
+func handleConn(conn net.Conn) error {
+	defer conn.Close()
+
+	if n, err := io.Copy(conn, conn); err != nil {
+		return err
+	} else {
+		_, _ = fmt.Fprintf(os.Stderr, "Copied %d bytes for %s\n", n, conn.RemoteAddr())
+	}
+
+	return nil
+}